McDonald’s is in some hot oil over its mozzarella sticks: According to CBS, the chain is now facing a class action lawsuit over the cheese in the deep-fried snack. The lawsuit, which was filed in federal court in California late last month, alleges that McDonald’s claim that the sticks are made with “100% real cheese” is false advertising, and that the sticks are made with a filer instead. The plaintiff is seeking a cool $5 million in damages.

The 32-page complaint alleges that the cheese in the mozzarella sticks is not completely mozzarella. Instead, the plaintiff claims the “sticks are filled with a substance that is composed (in part) of starch.” Delicious. The lawsuit says that the fast-food chain is breaking California’s unfair competition laws and false advertising law in an effort to cut costs. ABA Journal writes that the plaintiff had the mozzarella sticks tested and found that starch accounted for “3.76 percent of the cheese portion of the sticks… inside a breaded coating.” 

McDonald’s is vehemently defending its mozzarella sticks, which it introduced for $1.29 last summer. A spokesperson tells Law360: “Our mozzarella cheese sticks are made with 100 percent low-moisture part-skim mozzarella cheese… We intend to defend ourselves vigorously against these allegations.”

While the recently introduced all-day breakfast menu is going smoothly for McDonald’s, the mozzarella sticks have faced a few bumps. Last month, a number of reports started to emerge of people purchasing the snack and receiving hollow, breaded tubes lacking any cheese. McDonald’s attributed the issue to a “rollout glitch” where the cheese melted out of the sticks as they were being fried. The chain says they never should have been served to customers like that.

[via CBS]